Abstract: An automatic power factor correcting device for correcting the power factor of a load connected to a power line having a plurality of confuctors including a neutral conductor, a power line interface circuit for interfacing the device with the power line, a phase sensing circuit connected via the interface circuit to at least two of the conductors for sensing a phase shift between voltage and current in the two conductors. It further includes a phase correction circuit with a plurality of weighted capacitors, and capacitor connecting means having a control input connected to the phase sensing circuit for connecting at least one of the weighted capacitors to the power line for correcting the phase shift on the two conductors.